public byte[] Extract(DigitalAudio stegoAudio)
{
int[] primeSignal;
using (WavReader reader = new WavReader(File.OpenRead(PrimeSignalFilePath)))
primeSignal = reader.ReadAudio().GetSignal();
var stegoSignal = stegoAudio.GetSignal();
int samplesPerSegment = (int)Math.Floor((double)stegoSignal.Length / (MessageLength * 8));
var rnd = new Random(RandomSeed); int lseg, rseg;
int[] pseudoRandomSignal = new int[samplesPerSegment];
var difference = new double[samplesPerSegment];
List <bool> message = new List <bool>();
double primeMean = 0, difMean = 0;
for (int i = 0; (i + 1) * samplesPerSegment <= stegoSignal.Length; i++)
{
lseg = i * samplesPerSegment;
rseg = samplesPerSegment * (i + 1);
RndSignal(rnd, pseudoRandomSignal);
for (int j = lseg, k = 0; j < rseg; j++, k++)
{
primeSignal[j] = (int)(primeSignal[j] * 0.95);
difference[k] = (stegoSignal[j] - primeSignal[j]) * pseudoRandomSignal[k];
primeMean += primeSignal[j];
difMean += stegoSignal[j];
}
message.Add(Math.Sign(primeMean) == Math.Sign(difMean));
primeMean = 0; difMean = 0;
}
return(BitArrayToByteArray(new BitArray(message.ToArray())));
}
public void OpenWAV()
{
OutputLogs logs = OutputLogs.Instance();
OpenFileDialogService.Filter = "Wav Files (.wav)|*.wav|All Files (*.*)|*.*";
OpenFileDialogService.FilterIndex = 1;
OpenFileDialogService.Title = "Open target audio";
if (OpenFileDialogService.ShowDialog())
{
IFileInfo file = OpenFileDialogService.Files.First();
WavReader reader = null;
try
{
reader = new WavReader(File.Open(file.GetFullName(), FileMode.Open, FileAccess.Read, FileShare.None));
Audio = reader.ReadAudio();
AudioFileName = file.Name;
string msg = string.Concat("Succesfully loaded file - ", file.GetFullName());
logs.AddLog(new Message(MessageType.Info, msg, "WavReader"));
}
catch (ApplicationException ex)
{
logs.AddLog(new Message(MessageType.Error, ex.Message, ex.Source));
}
finally
{
if (reader != null)
{
reader.Dispose();
}
}
}
}
